Loom for circular weaving



Jan. 6, 1953 J. DUNOD 2,624,367

LOOM FOR CIRCULAR WEAVING I Filed Dec. 21, 1950 7 Sheets-Sheet l Jan. 6,1953 J. DUNOD 2,624,367

LOOM FOR CIRCULAR WEAVING Filed Dec. 21, 1950 1' Sheets-Sheet 2 6 co mAA, 0 54am;

7 Sheets-Sheet 3 J. DUNOD LOOM FOR CIRCULAR WEAVING .zfllflllll Jan. 6,1953 Filed Dec. 21, 1950 an m N 3 J. DUNOD LOOM FOR CIRCULAR WEAVINGJan. 6, 1953 7 Sheets-Sheet 4 Filed Dec. 21, 1950 Jan. 6, 1953 J. DUNODLOOM FOR CIRCULAR WEAVING FiIed Dec. 21, 1950 7 Sheets-Sheet 6 m wt fi lFLT X OW @m 2 m R. a? he W x m vm m Q? 3 &- '11 ll km -m N N W Wm .N 1 nm .0 km 0M 0 m I. I N m 3 S a 2 v N N g 3 3 3 Jan. 6, 1953 J. DUNOD LOOMFOR CIRCULAR WEAVING 7 Sheets-Sheet '7 Filed Dec. 21, 1950 Patented Jan.6, 1953 UNITED STATES PATENT OFFICE LOOM FOR CIRCULAR WEAVING JeanDunod, Paris, France Application December 21, 1950, Serial No. 201,964

' In France May 3, 1947 6 Claims.

My invention relates to a loom for circular weavin permitting of theweaving of natural or synthetic textile threads as well as metallicthreads, wherein:

(a) The warp threads are arranged along the generatrices of a verticalcylinder and are supplied by bobbins placed at one end (for example atthe bottom) of the loom, there being a number of bobbins equal to thatof the threads:

(b) The opening of the shed is controlled by harness.

This application constitutes a continuation-inpart of an earlier filedapplication, now abandoned, Serial No. 23,606, filed April 27, 1948.

My invention has for its object to provide a circular weaving loom withmeans, for opening the shed to permit the passage of the shuttle duringthe normal operation of the loom, and means for retracting all the Warpthreads towards one and same side of the reed in order to uncover theshuttle, for example to permit the re-loading of said shuttle.

One practical manner of carrying my invention into practice has beenillustrated diagrammatically and by way of example in the annexeddrawings:

Fig. 1 shows, in the system of harness according to my invention, oneheddle in the normal position, the point connected to the memberproducing the to-and-iro motion being most distant from the centre ofthe loom and the warp thread being on the outside of the shuttle.

Fig. 2 is similar, but the warp thread has been drawn towards the centreof the loom in order to uncover the shuttle.

Fig. 3 shows one heddle in the normal position, the point connected tothe member producing the to-and-fro motion being nearest to the centreand the warp thread being on the inside ofthe shuttle.

Fig. 4 is a view similar to Fig. 3 but corresponds to the position ofthe warp thread during the reloading of the shuttle.

, Figs. 5 to 7 are sections showing in three different positions how theinternal springs are secured to slides, and how some of said slides canbe arrested in the inner position. I

Fig. 8 is a plan view of the mechanism for retracting the warp threadsclear from the shuttle. Fig. 8a is a fragmental plan view at a largerscale.

Fig. 9 is a section on IX-IX in Fig. 8 with parts thereof showndiagrammatically.

Fig. 10 is a section on XX in Fig. 9.

. Fig. 11 is a perspective view of details of the mechanism shown inFigs. 9 and 10.

Fig. 12 is a fragmental plan showing the positionin g'of three differentslides shown in Figs. 5 to 7.

According to my invention, the harness proclucing the to-and-fro motionof the warp threads in order to normally open the shed during the normaloperation of the loom is controlled by cams, and each warp thread ispassed through an eye of a heddle, the harness comprising a number ofheddles equal to the number oi the warp threads. Each heddle isconnected through springs, on the one hand (towards the inside of theloom), to the element producing the to-andfro motion and, on the otherhand (towards the outside), to a point which is normally fixed but whichmay be displaced at will, the external spring being more powerful thanthe internal spring. A special arrangement of the heddles permits allthe warp threads to be drawn to one and the same side of the shuttle soas to be clear of the latter, and, in particular, to permit to replacethe spool carried by the shuttle.

Referring at first to Figs. 1 to 4, it will be noted that said figuresare merely diagrammatic and illustrate only the principle of theinvention. On said figures, 2 designates the warp thread, 3 the bobbinwhich supplies this thread, 5 the reed, 6 the shuttle, and 64 the weftthread. X-X is the axis of symmetry of the reed, and Y-Y is the axis ofthe loom driving shaft 50. Each heddle AB extends substantially in ahorizontal plane, which encounters the axis YY at the point 0, as seenin dotted line. This heddle is attached at A to an internal spring 3!and at B to an external spring 32. For sake of clearness, it will beassumed that the cam it producing the to-and-fro motion of each of theheddles is secured at O on the loom driving shaft 53 and acts upon amember 31 attached at D to the inner end of the spring 3 l. In Figs. 1to 4, I have shown only the cam 40 and the slide 3? with its roller 39.Similarly, for sake of clearness, only one stage of slides and heddleshas been shown, although practically the heddles are divided betweenseveral stages. The actual structures of said devices are shown indetail in Figs. 5 to 7.

The operation of the heddle is following: during the normal operation ofthe loom, it is necessary to open the shed of the warp threads 2, inorder to allow for the free passage of the shuttle. Consequently, theeye 69 of any one of the heddles is drawn from E to E i. e. from oneside of the reed 5 to the other side of said reed, and at the same timethe adjacent heddle is drawn from E to E, and conversely. When a warpthread 2 is in the position E shown in full line in Fig. 1, the nextwarp thread 2 coming from the bobbin 3 is in the position E shown indotted line in the same figure, i. e. symmetrical as to the axis X-X.Assuming that the heddle AB is directly attached to the driving member31, it would be positively reciprocated from E to E at each action ofsaid driving member. But it would be impossible to keep all the warpthreads retracted towards one and the same side of the reed, since atevery moment each two warp threads would be on one side of the line X-Xwhereas the other warp threads would be on theother-side.

According to my invention, it is possible to stop certain of the heddleswithout stopping the driving member, and consequently to retract towardsone side of the reed (for example towards the centre of the loom) allthe warp threads which, at a given moment, are positioned on the otherside of the reed, without at the .same time displacing towards theoutside of the loom the warp threads that already are on the inner sideof the reed. This result is achieved, according to my invention, bymeans of the mechanism that will be now described.

While the heddle AB is attached at A to an internal spring 3|, thislatter being itself attached at D to the sliding member 31, as disclosedabove, this heddle is attached to B to an external spring 32, the outerend C of this spring being attached at C to a semi-fixed point,"that isa point which may normally be considered as fixed, but which can, whennecessary, be displaced at will by means of a suitable control mechanismrepresented diagrammatically in Figs. 1 to 4 by a cable '34 passing overan idle pulley 35.

The spring 32 is stronger than the spring 3|. Said spring 32 can notexpand as long as the spring 31 is allowed to expand. But the expansionof the spring 3i is limited by a suitable tension limiting device 313.Said device 36 may be constituted by a tube forming a sheath, againstthe inner ends of which the ends 31a, 3 lb ofxthe spring 3! bear (Figs.1, 3 and 4). The device 36 may also be constituted by a flexible cablethe ends of which are attached to the ends of the spring 3 I. Suchtension limiting devices are well known in the art. The device 36 isdesigned for allowing a displacement AA=EE", equal to the opening of theshed. 7

It will thus be seen that, in normal operation, owing to the saidtension limiting device 36, the spring 3! behaves as a rigid connection,whilst the spring 32 absorbs the total motion of the heddles, since thepoint C is deemed to remain stationary.

Fig, 1 shows the position of the heddle and spring mechanism, in normaloperation, for the threads 2. Fig. 3 shows in the same conditions theposition of the threads 2. In this last figure, both springs 3i and 32are as much expanded as possible; it is assumed that the point'C isfixed.

Now supposing that it is desired for any reason, and particularly at thetime of re-loadin-g of the shuttle, to draw all of the warp threadstowards the centre of the loom, which has the effect of causing theshuttle to emerge from its cage of threads and to become located outsideof all the threads, it is necessary to bring to E thethreads 2 whichwould normally be at E at this time,

that is to say, to bring B to 'B and C to C for these threads (Fig. 2),without modifying the position of the member 31. This is efiected byreleasing (as described thereafter) the cable 34, and results inbringing to C the point C Without modifying the tension of the spring32.

The displacement of B (Fig. 1) to B (Fig. 2) is equal to thedisplacement of C to C and to that of E to E, since the tension of thespring 32 remains constant, the magnitude of the movement of theeccentric device from D to D being equal to the width EE of the reed andthe tension of the spring '3l' being maximum. But

it is evident that the displacement AA of the end of the heddle is equalto the distance EE', magnitude of the opening of the shed, and to thedistance 4C0, magnitude of the displacement of the point C; consequentlyThere aretwo cases:

(1) The point of attachment D of the spring 31 is in its positionfurthest removed from the point-0.

When the cable 34 is relieved, the spring 3|, which is .no longersubject to the action of the spring 32, collapses, drawing A to A andconsequently E to E (Fig. 2).

(2) The point-D of attachment of the-spring 3| is in its position Dnearestto the-centre'-:0 (case of thethreads 2 in Fig. 3)

The spring 3| is extended as much as allowed by the device 38. Theeye 69which was already at E does not shift (Fig. 3). The spring 32 isalso'ex-tended.

When the cable 34 is relieved, the point C is brought at C (Fig. i) andthe spring 32 (:01- lapses, the spring 31 remaining under the maximumtension.

It will be noted that, when the tensionon the cable 34 is relieved, thespring 32 remains collapsed; the point B remains stationary as well asthe heddle AB, and the end B of the spring 3! alone follows, between thepoints D and D, the motion of the device controlling the to-and-fromovement, the spring 3| being alternatively-col lapsed or expanded.

If now it is desired to re-establish the normal process of opening ofthe shed, it-will suffice to pull the cable 34 for moving the point C to0. Assuming that the mechanism had stopped in the position of Fig.4, thethreads '2 assume again the position of Fig. 3, and assuming that themechanism had stopped in the position of Fig. 2, thethreads 2 assumeagain the-position of Fig. 1.

From what has been said, it follows that the to-and-fro motion of themember 3! may be rendered inoperative on the threads as these threadshave been moved towards the internal edge of the reed. "If necessary, itwould also he possible to eifect this movement towards the external edgeby :a similar system, symmetrically disposed with respect to theaxis theprinciple of operation would be the same, but the actual structure ofthe reciprocating device 3-1, 39, M would be modified.

The displacement of the point C.;t0 C, that is to say the return of thewarp threads towards the internal edgeof the reed, "is-eitected inpractice by means of the mechanism illustrated Figs. 8 to 11 which willbe described thereafter.

I shall now refer to Figs. '5 to 7, order to indicate how the heddlesare attached -in--practice to the driving device, and how it isfurthermore possible, according to my invention, to produce differentkinds of weaves.

In viewof the considerable number of the heddles, a certain number ofthese heddles may be connected to one pair of springs 3| and 32, andthesesprings .are themselves divided between several levels or stages,as is shown in :Figs. 5 to '7.

In practice, thesprings 31 are generally housed in'the bores of slides'3l, 3l','3'!a, 31a (Figs. 5 to '7 and are securedat Dat the inner:ends:ofthese bores.

The slides mayconsist-of tubes-sliding in housings 38a arranged radiallyin a circular body 38 (Figs. 5 to -7and -'12) It will be seen that theslides may be arranged in the body 38 at several levels. Four stages ofslides 31, 31' and 31a, 31'a are to be seen in Figs. to '1. The slides31, 31' and their springs 3|, 3 correspond to a. first group of threadsand the slides 31a, 31'a and their springs 3|a, 3|a to a second group ofthreads. The slides 31, 31' on the one hand and 31a, 31a on the otherhand are connected together, respectively, by driving pins 52 and 52a,52' and 52'a, respectively secured to the slides 31, 31a and 31', 31aand projecting from each of said slides.

In the practice, the slides 31 and 31' as well as the correspondingheddles and springs 3|, 3| and 32 are connected to a single cable 34;the slides 31a, 31a, although being apparently in a same vertical planein Figs. 5 to 7 are, in fact, positioned under the slides 31, 31' but ina different angular setting, as viewed in Fig. 12. There are also onlytwo stages of slides in a given radial plane of the loom, and a singlecable 34 for each pair of slides. In Fig. 12, the cam 40 has beenomitted, and only its outer edge or track has been indicated in chainline.

Each slide 31 receives its to-and-fro motion from a roller 39 whichrolls upon the internal track of a cam 40. A second cam 40a offset by180 in relation to the first is arranged under the body 38 (Figs. 5 to7). It acts upon a roller 39a which issymmetrical in relation to theroller 39 and moves the slide 31a. The rollers 39, 39a are journalled onpivots 62, 62a secured to the slides 31, 31a and are maintained againstthe cams 40, 40a by the tension of the springs 3|.

It is to be noted that the circular body 38 is firmly secured to theframe of the loom (not shown) by any suitable means, the loom drivingshaft 50 rotating freely in a circular bore of said body, whilst thecams 46, 40a are keyed at 10 to the loom driving shaft.

In Figs. 5 to 7 and 12 the tension limiting devices 36 arediagrammatically shown and reciprocate with the slides, to which theyare secured at D. The arrangement of the springs 3| in the interior ofthe slides is necessary in the case of a loom of small diameter. In thecase of a loom of larger diameter, the springs 3| may be external to theslides.

According to my invention, it is possible to temporarily stop any one ofthe several stages of slides and consequently to produce different kindsof weaves.

Thus, I have provided a mechanism which would arrest, for example, oneof two stages alternatively or which would automatically arrest severalstages successively in a predetermined order depending upon the natureof the weave desired.

For example, in the case of Fig. 5, the slides 31 or 31a may continue tooperate, whilst the slides 31' and 31a are arrested in the innerposition (that of the slide 31'a). A suitable system of bolts 55, 55 and55a, 55a may be employed for arresting at will the slides 31, 31, 31aand 31'a.

In Figs. 5 to '7, it will be seen that each slide 31 is associated withan electromagnet 54 whose core 55 is biased by a spring 51 to protrudeoutwardly as a bolt for engagement with a notch 56 provided in the slide31, when the electromagnet 54 is not energized. Similar arrangements areprovided for the slides 31', 31a and 31a. The device operates asfollows: during the normal operation of the loom, all the slides 31, 31and 31a, 31'a are reciprocated. The electromagnets 54, 54a and 54', 54a,are energized, so that the cores or bolts 55, 55' and 55a, 55'a remainretracted against the springs 51, 51' and 51a, 51'a. Consequently, theslides 31, 31 on the one hand and 31a, 31'a on the other hand areconnected by the engagement of the driving pins 52, 52' and 52a, 52'a,and are reciprocated under the action of the roller and cam devices 39,40 and 39a, 400. (Fig. 5). But if it is desired to arrest for examplethe slides 31' and 31'a, the supply to the electromagnets 54 and 54a isinterrupted by the rotating commutator 58. Under the action of thesprings 51, 51a, the bolts 55',55a will come into engagement with thecorresponding notches 56, 56a as soon as the slides 31, 31'a in theiralternating motion are in their inner position (Fig. 6). Thus the slides31', 31'a are held in said inner position during the further motion ofthe slides 31, 31a, the engagement between the driving pins 52, 52' and52a, 52'! respectively being no more effective. In Fig. 6 there areshown the pins 52 and 52' separate from each other, the slide 31 beingat this moment in its outer position while the slide 3111 is at thismoment in its inner position. From Fig. 7 it can be viewed how it isalso possible to stop the motion of three stages of slides: 31, 31 and31a, by energizing only the electromagnet 54a so as to hold the bolt 55aretracted in the body 38. The electromagnet 54' does not need to beenergized, because the slide 31' is reciprocated only by the engagementof the driving pins 52, 52'. The rotating commutator 58 may be designed,as shown in the drawings, so as to energize temporarily theelectromagnets 54' and 54'a, so that the slides 31, 31'a may betemporarily arrested in the inner position according to the kind ofweave desired. It is of course impossible to arrest only the slides 31and 31a, since the slides 31' and 31a are reciprocated only by theslides 31 and 31a, by means of the pins 52, 52' and 52a, 52'a.

The mechanism for displacing the point C of attachment of the outer endof the external spring 32 will be now described, with reference to Figs.8 to 11.

Each heddle-tensioning spring 32 (or each pair of springs 32corresponding to two superposed stages 31, 31 or 31a, 31a of slides) isattached at its outer end to a cable 34 (Figs. 1 to 4 and 9) passingover two idle pulleys 35, and then over a pulley 43 and attachedfinallyat a fixed point 44 to the frame 42 of the loom (Fig. 9).

The pulleys 43 are mounted at the ends of slides 45 and 46 (in numberequal to that of the pairs of slides 31, 31' and 31a, 31'a, for exampleeighteen) arranged half and half, at two different levels on each sideof a diameter Z-'-Z (Figs. 8 and 9).

The slides carry rollers 41 which may bear against the internal tracksof a cam 48 keyed at 48a on the main driving shaft 50 of the loom andhaving two symmetrical crests.

It is to be noted that the stages of slides 45 and 46 as well as the cam48 are disposed concentric-ally with the stages of slides 31, 31a andcams 40, 40a, but at a different level: in Fig. 9, it will be seen thatthe slides 31, 31a are positioned above the slides 45, 46. But myinvention provides also for the slides 45, 46 being above the slides 31,31a.

In normal operation, the slides 45 and 46 are maintained clear from thecam 48 (in the position shown in Fig. 8) by means of latches 49 (Figs. 9to 11) which engage a groove 60 provided in the proximity of the innerend of each slide 45 or 46, and will be described thereafter.

A rotating commutator 6| supplied from a suit,

able source ,of current energizes two electromag nets ,55l acting .uponpins .53 ,slidably housed ;in the .rim of the cam 48 qfor renderinginoperative the latches49 (Figs. .8.,to ;11,),.

Each pin .53 is pivotably connected to a pushmember 63 by a ,pin .66(Fig. 8d). .Said pushmember is pivotably mounted at t lupon the upperface of the cam 48, and it is submitted to the .action or a mass 65, towhich it is pivotably connected'at 61. The mass .65 is biassed outwardlyby the centrifugal force, during the rotation of the cam '48., andconsequently causes the pushmember 63 to be retractedinwardly, thusbiassing the pin 53 inwardly (Figs. 8 and 8a) during the normaloperation of the loom.

Under these conditions, the cam 48, turning with .the vertical shaft'56, is normally inoperativeas to the rollers 41.

But if it is desired to move all the warp threads towards the centre,for example to free the shuttle for the purpose of permitting, itsre-loading, the rotating commutator ti (Figs. 8 and 9) is actuated andestablishes an exciting current'in the electromagnets at the instantwhen the symmetrical crests-of the cam 48 are passing the axis ZZ :(Fig.8). These electromagnets cause the pins 53 to emerge from the rim of thecam 48 against theaction of the mass 65 and push-member 63.

The mechanism for releasing the latches 49 is shown in part in Fig. 11.

In this figure, the bearing for mounting the slide 46 which at the sametime carriesthe pivot 59 of latch 49 has been omitted. It will vbeseenfrom Figs. 9 to 11 that each latch 49 engages normally a groove 69provided at the end .of the slide 46. As already stated, theelectromagnet 5|, when energized, causes the pin .53 .to protrudeoutwardly from the rim of the cam 48, and the rotation of this cam inthe direction of the :arrow brings the pin 53 into engagement withthelatch 49. This latch tilts about its pivot '59 and disengages thegroove 60 of the slide 45, thereby freeing the slide. The operation ofthe slide 45 is similar. As the release 'is efiected just at the instantwhen the crest of the ,cam 48 is passing under the corresponding roller,this operation takes :place without shock, since the slide continues inthis case to be held by its roller and by the crest of the cam in theposition in whichgit had previously been maintained by the latch 49. Theslides being free, the rollers 41 descend symmetrically along each ofthe two crests in proportion to the rotation of the cam 48.

It will thus be seen that, at the ,end of a half turn of the cam 28, allof the slides 45 .and 46 will be in their external positions andconsequently also that the pulleys 43 will. allow relaxation of thecables 34 tensioning the springs 32 and displacement towards the centre,to .C, of the ends C of thesesprings.

'The movement shown diagrammatically in Figs. 1 to 4 has thus beenrealised.

From this instant, the exciting current for the electromagnets .5! isinterrupted, whereby :the pins 53 are retracted into the rim of the cam48 due to the action of the masses E5. Asthe cam 48 continues itsrotation, the rollers zit? are acted upon by the second parts .of:itsitrack- The arrangement :which has inst :been .described :thus,permitsaof the drawing towards the centre ofall the warp threads insucha fashion as to .;free the ;-.s.hu t1e.

.It is to Joe noted that, as the control of the heddle 'by cam androllers permits (as has been seen above) of 'thearresting at the centreof any one group of slides 31, 310. or 37?, 3ia, itis possible to arrestall of the groups and as a result to bring all the threads to resttowards the inside part of the reed without having recourse to theauxiliary mechanism described above with reference to the Figs. 8 to 11,at the same time suppressing all of the external return springs 32(Figs. 1 to 4). In this case, the outer end B of each ,heddle A.-B wouldbe directly-attached as at 44 tothe frame Q2 of the loom. Theloclringand release of the slides 3?, 375a would then be eiTected by means ofthe mechanism illustrated in Figs. 5 t F1- The rotating commutator 58(Figs. '5 to 7) is actuated by suitable means which do not form a partof my invention. When the mechanism illustrated in Figs. 8 to 11 isassociated with the mechanism illustrated in Figs. 5 to '7, thecoinmutator .58 is designed for allowing the operation of the jloomaccording to the desired kind of weave, that is to say may beconstituted in the manner of the known perforated sheets for weavinglooms. But when .only the mechanism shown in Figs. 5 to '7 is used forretracting all the warp threads towards the centre of the loom inorderto uncover the shuttle, the rotating commutator 53 is designed-furt'l'lerrnore to keep all the warp threads retracted during there-loading of the shuttle, and in this case it is actuated by any knownsafety device, for example of the kind disclosed and claimed in mycopending U. S. Application Serial No. 23,607 filed April 25, 1948 whichis now Patent No. 2,587,982.

The rotating commutator ti is actuated, when the shuttle is to be-re-loaded, by any suitable means, for example by the device disclosedand claimed in my aforesaid U. S. Patent No. 2,587,982.

What I claim is:

'1. In-a circular weaving loom icr weaving textile or metal threadsmeans for normally controlling the opening of the shed formed .by-thewarp threads and for drawing all of the warp threads towards the centreof the loom in order to uncover the shuttle, which include a number ofheddles equal to that of the warp threads, means located inside the loomand adapted to produce at will a reciprocating movement of said heddles,springs operatively connecting said means to the inner ends of thecorresponding heddles, :furthersprings secured to the outer ends of the:heddles, and means for .adjustably securing the .outerends of lastmentioned springs in accordance -.with the desired opening and closingof the shed, the last mentioned springs being stronger than the first.mentioned springs.

2. In a circular weaving loom of the aforesaid type, heddles in numberequal to that of the warp threads, an axialiloorn driving shaft a cammember actuated by said shaft and arranged in a plane perpendicularthereto, at least one internal track on said cam member, slides arrangedin at least two different planes perpendicular to the loom :drivingshaft and adapted to assume a reciprocating movement, rollers journalledin said slides and adapted to roll upon said internal tracks on the cammember, means :for tom-.- -porarily arresting at least some otsaidslides in their innermost position, a plurality of encased springsradially positioned, each connecting operatively at least one heddlewith the corresponding slide, means for limiting the expansion of saidsprings, and means for connecting the outer end of the heddle to theframe of the loom.

3. In a circular weaving loom according to claim 2, external radialsprings each attached to the outer end of at least one heddle, aplurality of cables, attached on the one hand to the outer end of thecorresponding external spring and on the other hand to the frame of theloom, a plurality of idler and movable pulleys for said cables, eachcable passing over at least one idler and over -,a movable of saidpulleys, slides carrying said movable pulleys at their outer end anddistributed by halves in two planes perpendicular to the loom drivingshaft, bearings for mounting saidslides, a roller carried by each slideat its inner end, a cam actuated by said driving shaft, arranged in aplane perpendicular thereto and including aninternal track ofsymmetrical outlinei means for normally maintaining the rollers clear'from oi the track on the cam, and means for :causing said rollers tocooperate with said track.

4.: a circular weaving loom according to claim' 3, a groove on eachpulley carrying slide, a rocking latch cooperating with said groove andcarried by the bearing in which is mounted the corresponding slide, anelectromagnet system, means; for energizing same, pins in number equalto that of the electromagnets and slidably housed in the rim of the cam,for engaging said latches andftilting up same clear from thecorresponding groove in the slide when protruding outwardly;

under the action of the energized electromagnets,

10 cam and a lower cam with internal tracks, offset by 180, actuated bythe axial loom driving shaft and arranged in two parallel planesperpendicular thereto, four stages of superposed slides arranged inparallel planes perpendicular to the loom. driving shaft but disposed bypairs in different radial planes of the loom, a roller journalled on theupper face of each slide of the uppermost stage and cooperating with theupper cam track, a roller journalled on the lower face of each slide ofthe lowermost stage and cooperating with the lower cam track, means oneach uppermost, and on each lowermost slide for positively driving thecorresponding slide of each middle stage, bolts cooperating with notchesin the slides for locking each slide in its innermost position, springsfor biassing said bolts in engagement with the slides, electromagnetsfor retracting said bolts when energized, means including a rotatingcommutator for energizing at will said electromagnets, springsoperatively connecting push-members pivotably mounted upon the upperface of the cam and pivotably connected at one end :to said pins forbiassing normally inwardly said slides to the inner ends of thecorresponding heddles, and means for limiting the expansion of saidsprings.

6. In a circular weaving loom of the aforesaid type, heddles in numberequal to that of the warp threads, internal springs secured tothe innerends of the heddles, tension limiting devices for said springs, externalsprings stronger than the internal ones and secured to the outer ends ofthe heddles, a first cam member actuated by the loom driving shaft forreciprocating the heddles through slides and rollers, and a second cammember situated below the first one for displacing at will the outerends of the external spring through a mechanism including slides,rollers, cables and pulleys.

JEAN DUNOD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,016,370 Howarth Oct. 8, 19352,492,514 Ancet Dec. 27, 1949

